Noisy Tappet

[Shaft]

Please check, but I think the Typhoon needs solid lifters with adjustable push rods? I think?? Or was that the Hurricane?

[Guest Tim Norman]

I have the Hurricane and it uses Rhoads lifters and ordinary push rods, it is only just a little better than standard.

Doing a bit of research to see which will suit the car.

[Guest Tim Norman]

All sorted. Took it back to the beginning and set the preload properly.

Now sounds sweet as a nut. But the research done in the interim has lead me to plan the next upgrade to a different cam that should see me closer to the 300 bhp mark.

Then I need to get the revs down when cruising at 70. currently 3000rpm. Anyone get a Tremec box lying around?

[Bob Tucker]

You're never happy, are you...

[Guest Tim Norman]

Happy enough for now.

The cam swap can wit until the end of the year.

[Guest lotusPaul]

What spec is your current cam and what induction are you running

[Guest Tim Norman]

It's the Viper Hurricane acting on Rhoades lifters, a weber 500 on a performer manifold on some very trick heads, custom tubular exhausts with a power amp. All the gaskets and ports have been matched too. Base i=being the cross bolted 4L.

Considering the Pro 233 cam from V8 Tuner.

The Hurricane cam gives 20bhp over stock on a standard 3.5L

The Pro 233 gives 35bhp over stock on a standard 3.5L

[Guest lotusPaul]

On a standard 3.5, not impossible but certainly easier with more capacity. At least over 4.0 or you will find it arrives at high rpm and you may loose bottom end torque.

[Guest Tim Norman]

Cam in mind is strong in the mid range with the emphasis on top end power and torque. Power from 2000-6000 with a red line at 6500rpm.

Current spec was recently rolling roaded at 275bhp with 287ibft.up from 250bhp before the head change.

[Guest lotusPaul]

I would need to know your piston to valve clearances and air flow of heads along with exhaust details to properly spec a cam. But looking at what you have cam wise id say its a bit mild. You can have a lca of 110° +/- 2° with out causing a massive change, keeping the lift but extending the duration is old skool design tech so look at a cam that possibly has slightly more duration but more lift. Gives same "area under the curve" but less over lap and will maintain pressure in the combustion chamber. Better torque.

Or if you know your piston to valve clearance specs you could have one specialy ground at a price.

[Guest Tim Norman]

No idea on the head to valve clearance but I do know the Hurricane is only just better than standard.

The cam I am thinking about has:

INTAKE duration of 280 degrees, lift 0.485"

EXHAUST Duration 286 degrees, lift .50"
Lobe separation 112 degrees

 

The heads are Warrior heads from V8 Developments, Which are about as good as you can get without paying "really silly" money.

Edited March 12, 2017 by Tim Norman

[Guest lotusPaul]

Piper cams normally do something around 276 and 286° duration. Ive used thier cams before and been happy. Your limitations would be your followers. Give them a look.

 

Personaly id go mid 270° but thats just me, if a mid 280° had more lift you could always get that re profiled and have the duration of the 270 with the lift of the 280.

[Guest Tim Norman]

Crower

[Guest Tim Norman]

Finally got it all back together. Needed 32 thou shims under the pedestals rather than the 16 thou previously. Just took it for a road test, the first since I had the new heads and rolling road.

At low speeds, the tappety noise is still there, probably the same as before but now I am more aware of it. However, once I got on to the open road and literally stamped on the loud pedal my mind was taken way from the potential noise of the tappets as the speed became my primary concern and the rate at which I was going through the gears!

 

The last car I was in that accelerated like that was an F Type! I went through them that quick I actually went for 6th! Can you get 6 in a Rover Box?

Edited March 19, 2017 by Tim Norman

[Guest lotusPaul]

Tim

 

Sounds like your loving that v8 torque. I had a look a crower cams, dont know which one you would want a look at. I had a thought that if you could check the amount of lift you had at your valve with your current setup, and considered how much further you could go before getting coil binding, then you would be able to work out a max lift at valve. Now providing that doesnt hit your piston crown you could use that dimension to spec a cam lift bassed on your engines own limitations. Then maybe cross check that with a web search and see if an off the shelf item is available.

 

My concern is your not getting the most out off them heads of yours. Hopefully you should see some improvement with clearences sorted.